NEW YORK (CNNMoney.com) -- Stocks rallied Thursday in a broad-based advance as a strong report on economic growth in the third quarter reassured investors that the recovery is on track.

The Dow Jones industrial average (INDU) gained just shy of 200 points, or 2%, closing at 9962.58. It was the Dow's biggest one-day percentage gain since July 15, and came exactly 80 years after Wall Street's darkest day, the Crash of 1929.

The Dow and S&P ended three of the last four sessions lower, and the Nasdaq declined in all four, as investors turned cautious after a seven-month stock rally. Early enthusiasm about better-than-expected third-quarter profit gave way to questions about the strength of the economy, causing investors to pull back.

The S&P 500 lost 5% between the rally peak on Oct. 19 and Wednesday's close. Both the better-than-expected GDP report and the preceding sharp, short selloff gave stocks a boost Thursday. Since bottoming at a 12-year low on March 9, the S&P 500 has gained 57.6% as of Thursday's close.

Reports on personal income and spending, consumer sentiment and manufacturing are all due Friday morning.

Economy: GDP grew at a 3.5% annualized rate in the third quarter, the government reported Thursday. That was better than the 3.2% rate economists surveyed by Briefing.com had predicted and also marked the first quarter of growth in a year. GDP fell at a 0.7% rate in the second quarter.

Some organic factors fueled the advance, including a slowdown in the pace of businesses reducing inventories. But other short-term factors played a role too, including the impact of government stimulus programs such as Cash for Clunkers. Yet some economists are concerned that when those short-term factors are removed, any recovery could be pretty flimsy.

"It was a little better than expected, but you have to wonder how much of the growth was pulled from another quarter, with the stimulus driving so much of it," said Drew Kanaly, chairman and CEO at Kanaly Trust.

"As you look to quarters down the road, you have to wonder how sustainable this level of GDP is," he said. "Can the government take away all the stimulus and make that handoff to the private sector?"

A separate government report showed that the number of Americans filing new claims for unemployment fell to 530,000 last week from 531,000 the previous week. Economists thought it would drop to 525,000.

Continuing claims, a measure of Americans receiving benefits for a week or more, fell to 5,797,000 from 5,945,000 the week before. Economists thought claims would fall to 5,905,000.

Market breadth was positive. On the New York Stock Exchange, winners beat losers four to one on volume of 1.45 billion shares. On the Nasdaq, advancers topped decliners nine to four on 2.33 billion shares.